Image capturing optical system

ABSTRACT

This invention provides an image capturing optical system in order from an object side to an image side comprising: a first lens element with positive refractive power having a convex object-side surface; a second lens element; a third lens element; a fourth lens element with both the object-side and image-side surfaces thereof being aspheric, and the fourth lens element is made of plastic; and a fifth lens element with negative refractive power, both the object-side and image-side surfaces thereof being aspheric, at least one inflection point is formed on at least one of the object-side and image-side surfaces thereof, and the fifth lens element is made of plastic. By such arrangement, photosensitivity and total track length of the system can be reduced, and better image quality can be obtained.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(a)on Patent Application No. 100,123,802 filed in Taiwan, R.O.C. on Jul. 6,2011, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image capturing optical system, andmore particularly, to a compact image capturing optical system used inelectronic products.

2. Description of the Prior Art

In recent years, with the popularity of portable electronic productshaving photographing function, the demand of compact imaging lens systemhas grown. Generally, the sensor of a general photographing camera isnone other than CCD (Charge Coupled Device) or CMOS device(Complementary Metal Oxide Semiconductor device). Furthermore, advancesin semiconductor manufacturing technology have allowed the pixel size ofsensors to be reduced and therefore lead compact imaging lens systems tohigher resolution. In the meantime, the demand for better image qualityis also increased.

A conventional imaging lens system with high imaging power, such as theone set forth in U.S. Pat. No. 7,365,920, generally has a front stop andfour lens elements; wherein, the first and second lens elements areadhered together to form a doublet for correcting the chromaticaberration. However, this kind of arrangement has the followingdisadvantages. First, the degree of freedom in arranging the lens systemis curtailed due to the employment of excessive number of sphericalglass lenses; thus, the total track length of the system cannot bereduced easily. Second, the process of adhering glass lenses together iscomplicated, posing difficulties in manufacturing. Moreover, thepopularity of high-class portable devices such as Smart Phone and PDA(Personal Digital Assistant) drives the rapid improvements in highresolution and image quality of the current compact imaging lenssystems, conventional four lens elements systems no longer satisfy thehigher level camera modules. On the other hand, a conventional imagecapturing lens system with five lens elements usually has thedisadvantage of having an excessively long total track length, andthereby is not suitable for compact electronic devices.

Inasmuch as the foregoing, a need is continuously existed for a lenssystem with good image quality and moderate total track length and issuitable for applying for compact and portable electronic products.

SUMMARY OF THE INVENTION

The present invention provides an image capturing optical systemcomprising, in order from an object side to an image side: a first lenselement with positive refractive power having a convex object-sidesurface; a second lens element; a third lens element; a fourth lenselement with both the object-side and image-side surfaces thereof beingaspheric, and the fourth lens element is made of plastic; and a fifthlens element with negative refractive power, both the object-side andimage-side surfaces thereof being aspheric, at least one inflectionpoint is formed on at least one of the object-side and image-sidesurfaces thereof, and the fifth lens element is made of plastic; whereina focal length of the image capturing optical system is f, a focallength of the fifth lens element is f5, and they satisfy the followingrelation: −5.0<f/f5<−3.0.

On the other hand, the present invention provides an image capturingoptical system comprising, in order from an object side to an imageside: a first lens element with positive refractive power having aconvex object-side surface; a second lens element with negativerefractive power; a third lens element; a fourth lens element withpositive refractive power, a convex image-side surface, both theobject-side and image-side surfaces thereof being aspheric, and thefourth lens element is made of plastic; and a fifth lens element withnegative refractive power, a concave image-side surface, both theobject-side and image-side surfaces thereof being aspheric, at least oneinflection point is formed on at least one of the object-side andimage-side surfaces thereof, and the fifth lens element is made ofplastic; wherein a focal length of the image capturing optical system isf, a focal length of the fifth lens element is f5, and they satisfy thefollowing relation: −5.0<f/f5<−3.0.

By such arrangement, photosensitivity and total track length of thesystem can be reduced, and better image quality can be obtained.

In the aforementioned image capturing optical system, the first lenselement has positive refractive power and thereby can provide refractivepower needed for the system and is favorable for reducing the totaltrack length thereof. When the second lens element has negativerefractive power, the aberration produced by the first lens element withpositive refractive power can be effectively corrected. When the fourthlens element has positive refractive power, the refractive power of thefirst lens element can be effectively distributed for reducing thesensitivity of the system. Moreover, when the fourth lens element haspositive refractive power and the fifth lens element has negativerefractive power, a positive-negative telephoto structure is formed sothat the back focal length of the system is favorably reduced forshortening the total track length of the system.

In the aforementioned image capturing optical system, the first lenselement can be a bi-convex lens element or a meniscus lens elementhaving a convex object-side surface and a concave image-side surface.When the first lens element is a bi-convex lens element, the refractivepower of the first lens element can be strengthened for reducing thetotal track length of the system. When the first lens element is aconvex-concave meniscus lens element, it is favorable for correcting thespherical aberration of the system. When the second lens element is aconvex-concave meniscus lens element, the aberrations produced by thefirst lens element can be favorably corrected and the refractive powerof the second lens element can be effectively controlled for correctingthe aberration of the system. When the fourth lens element has a concaveobject-side surface and a convex image-side surface, the astigmatism canbe effectively corrected and the positive refractive power of the fourthlens element can be effectively adjusted for reducing the errorsensitivity of the optical lens system. When the fifth lens element hasa concave object-side surface, the negative refractive power of thefifth lens element can be properly adjusted to cooperate with the fourthlens element for obtaining the telephoto effect. When the fifth lenselement has a concave image-side surface, the principal point of thesystem can be positioned away from the image plane, and the back focallength of the system can be reduced for favorably shortening the totaltrack length thereof and keeping the system compact. Furthermore, whenat least one inflection is formed on the fifth lens element, the angleat which light projects onto the image sensor from the off-axis fieldcan be effectively reduced so that the sensing efficiency of the imagesensor can be improved and the off-axis aberration can be corrected.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows an image capturing optical system in accordance with afirst embodiment of the present invention.

FIG. 1B shows the aberration curves of the first embodiment of thepresent invention.

FIG. 2A shows an image capturing optical system in accordance with asecond embodiment of the present invention.

FIG. 2B shows the aberration curves of the second embodiment of thepresent invention.

FIG. 3A shows an image capturing optical system in accordance with athird embodiment of the present invention.

FIG. 3B shows the aberration curves of the third embodiment of thepresent invention.

FIG. 4A shows an image capturing optical system in accordance with afourth embodiment of the present invention.

FIG. 4B shows the aberration curves of the fourth embodiment of thepresent invention.

FIG. 5A shows an image capturing optical system in accordance with afifth embodiment of the present invention.

FIG. 5B shows the aberration curves of the fifth embodiment of thepresent invention.

FIG. 6A shows an image capturing optical system in accordance with asixth embodiment of the present invention.

FIG. 6B shows the aberration curves of the sixth embodiment of thepresent invention.

FIG. 7A shows an image capturing optical system in accordance with aseventh embodiment of the present invention.

FIG. 7B shows the aberration curves of the seventh embodiment of thepresent invention.

FIG. 8A shows an image capturing optical system in accordance with aneighth embodiment of the present invention.

FIG. 8B shows the aberration curves of the eighth embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides an image capturing optical systemcomprising, in order from an object side to an image side: a first lenselement with positive refractive power having a convex object-sidesurface; a second lens element; a third lens element; a fourth lenselement with both the object-side and image-side surfaces thereof beingaspheric, and the fourth lens element is made of plastic; and a fifthlens element with negative refractive power, both the object-side andimage-side surfaces thereof being aspheric, at least one inflectionpoint is formed on at least one of the object-side and image-sidesurfaces thereof, and the fifth lens element is made of plastic; whereina focal length of the image capturing optical system is f, a focallength of the fifth lens element is f5, and they satisfy the followingrelation: −5.0<f/f5<−3.0.

When the relation of −5.0<f/f5<−3.0 is satisfied, the fifth lens elementof the present invention can be configured with stronger negativerefractive power, which can effectively correct the high orderaberration produced by the system for obtaining better image quality;preferably, the following relation is satisfied: −4.5<f/f5<−3.2; morepreferably, the following relation is satisfied: −4.5<f/f5<−3.4.

In the aforementioned image capturing optical system, a curvature radiusof the object-side surface of the second lens element is R3, a curvatureradius of the image-side surface of the second lens element is R4, andthey preferably satisfy the following relation: 1.5<(R3+R4)/(R3−R4)<4.5.When the above relation is satisfied, the curvature of the second lenselement is more suitable and thereby the aberration of the system can becorrected favorably.

In the aforementioned image capturing optical system, the focal lengthof the image capturing optical system is f, a focal length of the thirdlens element is f3, and they preferably satisfy the following relation:−0.5<f/f3<0.5. When the above relation is satisfied, the third lenselement can effectively distribute the refractive power required for thesystem and thereby reduce the sensitivity of the system.

In the aforementioned image capturing optical system, a centralthickness of the fourth lens element is CT4, a central thickness of thefifth lens element is CT5, and they preferably satisfy the followingrelation: 2.5<CT4/CT5<4.5. When the above relation is satisfied, thearrangement of the thickness of the fourth lens element and the fifthlens element is more balance for keeping the compact property and isfavorable for manufacturing.

In the aforementioned image capturing optical system, a curvature radiusof the image-side surface of the fourth lens element is R8, the focallength of the image capturing optical system is f, and they preferablysatisfy the following relation: −0.25<R8/f<−0.05. When the aboverelation is satisfied, appropriate positive refractive power can beobtained by the arrangement of the curvature radius of the image-sidesurface of the fourth lens element, and thereby the error sensitivity ofthe system can be favorably reduced. Also, the positive refractive powerof the fourth lens element can complement with the negative refractivepower of the fifth lens element for providing telephoto effect.

In the aforementioned image capturing optical system, the system furthercomprises a stop, an axial distance between the stop and the image-sidesurface of the fifth lens element is SD, an axial distance between theobject-side surface of the first lens element and the image-side surfaceof the fifth lens element is TD, and they preferably satisfy thefollowing relation: 0.75<SD/TD<1.1. When the above relation issatisfied, a better balance between the properties of telecentricity andwide field of view can be favorably obtained.

In the aforementioned image capturing optical system, an axial distancebetween the second lens element and the third lens element is T23, anaxial distance between the third lens element and the fourth lenselement is T34, a central thickness of the third lens element is CT3,and they preferably satisfy the following relation:2.0<(T23+T34)/CT3<4.0. When the above relation is satisfied, thearrangement for each lens element is more suitable for manufacturingwith an appropriate total track length.

In the aforementioned image capturing optical system, the system furthercomprises an image sensor provided on an image plane, an axial distancebetween the object-side surface of the first lens element and the imageplane is TTL, half of a diagonal length of an effective photosensitivearea of the image sensor is ImgH, and they preferably satisfy thefollowing relation: TTL/ImgH<2.0. When the above relation is satisfied,it is favorable for keeping the system compact in order to be equippedon portable electronic products.

In the aforementioned image capturing optical system, an Abbe number ofthe first lens element is V1, an Abbe number of the second lens elementis V2, and they preferably satisfy the following relation: 30<V1−V2<42.When the above relation is satisfied, the chromatic aberration of thesystem can be corrected favorably.

In the aforementioned image capturing optical system, the focal lengthof the image capturing optical system is f, a focal length of the fourthlens element is f4, the focal length of the fifth lens element is f5,and they preferably satisfy the following relation:5.0<|f/f4|+|f/f5|<8.0. When the above relation is satisfied, thearrangement of the refractive power of the fourth lens element and thefifth lens element is more balanced, and thereby the sensitivity of thesystem can be favorably reduced and the fourth lens element and thefifth lens element can complement with each other for providingtelephoto effect, which can reduce the back focal length of the system.

In the aforementioned image capturing optical system, a curvature radiusof the object-side surface of the fifth lens element is R9, a curvatureradius of the image-side surface of the fifth lens element is R10, andthey preferably satisfy the following relation:−0.8<(R9+R10)/(R9−R10)<0.4. When the above relation is satisfied, thecurvature of the fifth lens element is more suitable, and thereby afifth lens element with stronger negative refractive power can beconfigured for correcting the high order aberration of the systemfavorably.

On the other hand, the present invention provides an image capturingoptical system comprising, in order from an object side to an imageside: a first lens element with positive refractive power having aconvex object-side surface; a second lens element with negativerefractive power; a third lens element; a fourth lens element withpositive refractive power, a convex image-side surface, both theobject-side and image-side surfaces thereof being aspheric, and thefourth lens element is made of plastic; and a fifth lens element withnegative refractive power, a concave image-side surface, both theobject-side and image-side surfaces thereof being aspheric, at least oneinflection point is formed on at least one of the object-side andimage-side surfaces thereof, and the fifth lens element is made ofplastic; wherein a focal length of the image capturing optical system isf, a focal length of the fifth lens element is f5, and they satisfy thefollowing relation: −5.0<f/f5<−3.0.

When the relation of −5.0<f/f5<−3.0 is satisfied, the fifth lens elementof the present invention can be configured with stronger negativerefractive power, which can effectively correct the high orderaberration produced by the system for obtaining better imaging quality;preferably, the following relation is satisfied: −4.5<f/f5<−3.2.

In the aforementioned image capturing optical system, a curvature radiusof the image-side surface of the fourth lens element is R8, the focallength of the image capturing optical system is f, and they preferablysatisfy the following relation: −0.25<R8/f<−0.05. When the aboverelation is satisfied, appropriate positive refractive power can beobtained by the arrangement of the curvature radius of the image-sidesurface of the fourth lens element, and thereby the error sensitivity ofthe system can be favorably reduced. Also, the positive refractive powerof the fourth lens element can complement with the negative refractivepower of the fifth lens element for providing telephoto effect.

In the aforementioned image capturing optical system, the focal lengthof the image capturing optical system is f, a focal length of the fourthlens element is f4, the focal length of the fifth lens element is f5,and they preferably satisfy the following relation:5.0<|f/f4|+|f/f5|<8.0. When the above relation is satisfied, thearrangement of the refractive power of the fourth lens element and thefifth lens element is more balance, and thereby the sensitivity of thesystem can be favorably reduced and the fourth lens element and thefifth lens element can complement with each other for providingtelephoto effect, which can reduce the back focal length of the system.

In the aforementioned image capturing optical system, the lens elementscan be made of glass or plastic material. If the lens elements are madeof glass, the freedom for distributing the refractive power of the imagecapturing optical system can be increased. If plastic material isadopted to produce the lens elements, the production cost will bereduced effectively. Additionally, the surfaces of the lens elements canbe aspheric and easily made into non-spherical profiles, allowing moredesign parameter freedom which can be used to reduce aberrations and thenumber of the lens elements used in an optical system. Consequently, thetotal track length of the image capturing optical system can beeffectively reduced.

In the present image capturing optical system, if a lens element has aconvex surface, it means the portion of the surface in proximity to theoptical axis is convex; if a lens element has a concave surface, itmeans the portion of the surface in proximity to the optical axis isconcave.

In the present image capturing optical system, there can be at least onestop, such as a glare stop or a field stop, provided for eliminatingstray light and thereby promoting image resolution thereof.

In the present image capturing optical system, the stop can beconfigured as a front stop or a middle-placed stop. A front stop canprovide a longer distance between an exit pupil of the system and animage plane and can improve the image-sensing efficiency of an imagesensor of CCD or CMOS. A middle-placed stop is favorable for enlargingthe field of view of the system and thereby provides a wide field ofview for the same.

Preferred embodiments of the present invention will be described in thefollowing paragraphs by referring to the accompanying drawings.

Embodiment 1

FIG. 1A shows an image capturing optical system in accordance with thefirst embodiment of the present invention, and FIG. 1B shows theaberration curves of the first embodiment of the present invention. Theimage capturing optical system of the first embodiment of the presentinvention mainly comprises five lens elements, in order from an objectside to an image side:

a first lens element 110 made of plastic with positive refractive powerhaving a convex object-side surface 111 and a concave image-side surface112, the object-side and image-side surfaces 111 and 112 thereof beingaspheric;

a second lens element 120 made of plastic with negative refractive powerhaving a convex object-side surface 121 and a concave image-side surface122, the object-side and image-side surfaces 121 and 122 thereof beingaspheric;

a third lens element 130 made of plastic with positive refractive powerhaving a concave object-side surface 131 and a convex image-side surface132, the object-side and image-side surfaces 131 and 132 thereof beingaspheric;

a fourth lens element 140 made of plastic with positive refractive powerhaving a concave object-side surface 141 and a convex image-side surface142, the object-side and image-side surfaces 141 and 142 thereof beingaspheric; and

a fifth lens element 150 made of plastic with negative refractive powerhaving a concave object-side surface 151 and a concave image-sidesurface 152, the object-side and image-side surfaces 151 and 152 thereofbeing aspheric, and at least one inflection point is formed on both theobject-side surface 151 and the image-side surface 152 thereof;

wherein an aperture stop 100 is disposed between the first lens element110 and the second lens element 120;

the image capturing optical system further comprises an IR filter 160disposed between the image-side surface 152 of the fifth lens element150 and an image plane 171, and the IR filter 160 is made of glass andhas no influence on the focal length of the image capturing opticalsystem; the image capturing optical system further comprises an imagesensor 170 provided on the image plane 171.

The detailed optical data of the first embodiment is shown in TABLE 1,and the aspheric surface data is shown in TABLE 2, wherein the units ofthe radius of curvature, the thickness and the focal length areexpressed in mm, and HFOV is half of the maximal field of view.

TABLE 1 (Embodiment 1) f = 4.33 mm, Fno = 2.85, HFOV = 33.5 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # length 0Object Plano Infinity 1 Lens 1   1.664200 (ASP) 0.533 Plastic 1.544 55.93.54 2 10.876400 (ASP) 0.050 3 Ape. Stop Plano 0.050 4 Lens 2   3.113300(ASP) 0.250 Plastic 1.634 23.8 -6.88 5   1.759550 (ASP) 0.480 6 Lens 3-39.859100 (ASP) 0.428 Plastic 1.544 55.9 19.74 7  -8.493500 (ASP) 0.6188 Lens 4  -9.663100 (ASP) 0.941 Plastic 1.544 55.9 1.68 9  -0.865750(ASP) 0.221 10 Lens 5  -1.423360 (ASP) 0.280 Plastic 1.544 55.9 -1.37 11  1.680830 (ASP) 0.500 12 IR-filter Plano 0.300 Glass 1.517 64.2 — 13Plano 0.490 14 Image Plano — * Reference wavelength is d-line 587.6 nm

TABLE 2 Aspheric Coefficients Surface # 1 2 4 5 6 k = 8.33767E−01−3.90332E+01 1.21872E+00 2.03126E+00 4.86797E+01 A4 = −1.58232E−02−5.27194E−02 −2.04864E−01 −1.94118E−01 −8.09187E−02 A6 = 3.16938E−041.25386E−01 3.13222E−01 2.12571E−01 4.62327E−03 A8 = 1.90293E−021.88684E−02 −1.52843E−01 −1.99473E−01 5.20006E−02 A10 = −5.07980E−02−1.09040E−01 −1.11414E−01 8.67946E−02 −3.08929E−02 A12 = 5.91719E−021.38384E−01 1.47237E−01 −7.44427E−02 2.67335E−02 A14 = −5.98706E−03−3.21924E−02 −4.62316E−02 2.34564E−02 −6.97206E−03 Surface # 7 8 9 10 11k = 7.54311E+00 −4.88982E+01 −3.79352E+00 −9.21378E+00 −1.71541E+01 A4 =−8.28529E−02 −8.97340E−02 −7.31056E−02 −4.01086E−02 −3.57146E−02 A6 =1.53407E−02 1.16317E−02 2.59666E−02 3.20483E−03 4.81697E−03 A8 =−9.65766E−03 −1.94228E−02 −1.31784E−02 1.66134E−03 −8.15651E−04 A10 =1.31648E−02 1.12452E−03 7.66627E−04 −2.30318E−04 2.65513E−05 A12 =1.02690E−03 1.02765E−03 5.36162E−04 9.75220E−06 6.45422E−06 A14 =−2.51979E−05 −3.01649E−04 3.72636E−07 −7.38679E−07 −2.63112E−07

The equation of the aspheric surface profiles is expressed as follows:

${X(Y)} = {{\left( {Y^{2}/R} \right)/\left( {1 + {{sqrt}\left( {1 - {\left( {1 + k} \right)*\left( {Y/R} \right)^{2}}} \right)}} \right)} + {\sum\limits_{i}{({Ai})*\left( Y^{i} \right)}}}$

wherein:

X: the height of a point on the aspheric surface at a distance Y fromthe optical axis relative to the tangential plane at the asphericsurface vertex;

Y: the distance from the point on the curve of the aspheric surface tothe optical axis;

k: the conic coefficient;

Ai: the aspheric coefficient of order i.

In the first embodiment of the present image capturing optical system,the focal length of the image capturing optical system is f, and itsatisfies the following relation: f=4.33 (mm).

In the first embodiment of the present image capturing optical system,the f-number of the image capturing optical system is Fno, and itsatisfies the relation: Fno=2.85.

In the first embodiment of the present image capturing optical system,half of the maximal field of view of the image capturing optical systemis HFOV, and it satisfies the relation: HFOV=33.5 deg.

In the first embodiment of the present image capturing optical system,an Abbe number of the first lens element 110 is V1, an Abbe number ofthe second lens element 120 is V2, and they satisfy the followingrelation: V1−V2=32.1.

In the first embodiment of the present image capturing optical system, acentral thickness of the fourth lens element 140 is CT4, a centralthickness of the fifth lens element 150 is CT5, and they satisfy thefollowing relation: CT4/CT5=3.36.

In the first embodiment of the present image capturing optical system,an axial distance between the second lens element 120 and the third lenselement 130 is T23, an axial distance between the third lens element 130and the fourth lens element 140 is T34, a central thickness of the thirdlens element 130 is CT3, and they satisfy the following relation:(T23+T34)/CT3=2.57.

In the first embodiment of the present image capturing optical system, acurvature radius of the object-side surface 121 of the second lenselement 120 is R3, a curvature radius of the image-side surface 122 ofthe second lens element 120 is R4, and they satisfy the followingrelation: (R3+R4)/(R3−R4)=3.60.

In the first embodiment of the present image capturing optical system, acurvature radius of the object-side surface 151 of the fifth lenselement 150 is R9, a curvature radius of the image-side surface 152 ofthe fifth lens element 150 is R10, and they satisfy the followingrelation: (R9+R10)/(R9−R10)=−0.08.

In the first embodiment of the present image capturing optical system, acurvature radius of the image-side surface 142 of the fourth lenselement 140 is R8, the focal length of the image capturing opticalsystem is f, and they satisfy the following relation: R8/f=−0.20.

In the first embodiment of the present image capturing optical system,the focal length of the image capturing optical system is f, a focallength of the third lens element 130 is f3, and they satisfy thefollowing relation: f/f3=0.22.

In the first embodiment of the present image capturing optical system,the focal length of the image capturing optical system is f, a focallength of the fifth lens element 150 is f5, and they satisfy thefollowing relation: f/f5=−3.16.

In the first embodiment of the present image capturing optical system,the focal length of the image capturing optical system is f, a focallength of the fourth lens element 140 is f4, the focal length of thefifth lens element 150 is f5, and they satisfy the following relation:|f/f4|+|f/f5|=5.73.

In the first embodiment of the present image capturing optical system,an axial distance between the aperture stop 100 and the image-sidesurface 152 of the fifth lens element 150 is SD, an axial distancebetween the object-side surface 111 of the first lens element 110 andthe image-side surface 152 of the fifth lens element 150 is TD, and theysatisfy the following relation: SD/TD=0.85.

In the first embodiment of the present image capturing optical system,an axial distance between the object-side surface 111 of the first lenselement 110 and the image plane 171 is TTL, half of a diagonal length ofan effective photosensitive area of the image sensor 170 is ImgH, andthey satisfy the following relation: TTL/ImgH=1.76.

Embodiment 2

FIG. 2A shows an image capturing optical system in accordance with thesecond embodiment of the present invention, and FIG. 2B shows theaberration curves of the second embodiment of the present invention. Theimage capturing optical system of the second embodiment of the presentinvention mainly comprises five lens elements, in order from an objectside to an image side:

a first lens element 210 made of plastic with positive refractive powerhaving a convex object-side surface 211 and a concave image-side surface212, the object-side and image-side surfaces 211 and 212 thereof beingaspheric;

a second lens element 220 made of plastic with negative refractive powerhaving a convex object-side surface 221 and a concave image-side surface222, the object-side and image-side surfaces 221 and 222 thereof beingaspheric;

a third lens element 230 made of plastic with positive refractive powerhaving a convex object-side surface 231 and a convex image-side surface232, the object-side and image-side surfaces 231 and 232 thereof beingaspheric;

a fourth lens element 240 made of plastic with positive refractive powerhaving a concave object-side surface 241 and a convex image-side surface242, the object-side and image-side surfaces 241 and 242 thereof beingaspheric; and

a fifth lens element 250 made of plastic with negative refractive powerhaving a concave object-side surface 251 and a concave image-sidesurface 252, the object-side and image-side surfaces 251 and 252 thereofbeing aspheric, and at least one inflection point is formed on both theobject-side surface 251 and the image-side surface 252 thereof;

wherein an aperture stop 200 is disposed between the first lens element210 and the second lens element 220;

the image capturing optical system further comprises an IR filter 260disposed between the image-side surface 252 of the fifth lens element250 and an image plane 271, and the IR filter 260 is made of glass andhas no influence on the focal length of the image capturing opticalsystem; the image capturing optical system further comprises an imagesensor 270 provided on the image plane 271.

The detailed optical data of the second embodiment is shown in TABLE 3,and the aspheric surface data is shown in TABLE 4, wherein the units ofthe radius of curvature, the thickness and the focal length areexpressed in mm, and HFOV is half of the maximal field of view.

TABLE 3 (Embodiment 2) f = 4.35 mm, Fno = 2.85, HFOV = 33.1 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # length 0Object Plano Infinity 1 Lens 1  1.727753 (ASP) 0.541 Plastic 1.535 56.33.58 2 15.933402 (ASP) 0.035 3 Ape. Stop Plano 0.080 4 Lens 2  3.249075(ASP) 0.286 Plastic 1.650 21.4 -6.41 5  1.761559 (ASP) 0.458 6 Lens 324.574178 (ASP) 0.430 Plastic 1.544 55.9 11.63 7  -8.473051 (ASP) 0.6208 Lens 4  -8.716875 (ASP) 1.184 Plastic 1.535 56.3 1.53 9  -0.781277(ASP) 0.179 10 Lens 5  -1.067128 (ASP) 0.317 Plastic 1.535 56.3 -1.21 11  1.828325 (ASP) 0.400 12 IR-filter Plano 0.300 Glass 1.517 64.2 — 13Plano 0.425 14 Image Plano — * Reference wavelength is d-line 587.6 nm

TABLE 4 Aspheric Coefficients Surface # 1 2 4 5 6 k = 8.62368E−015.03972E+00 1.34511E+00 2.07894E+00 −1.00000E+00 A4 = −1.32490E−02−5.46477E−02 −2.06567E−01 −2.11677E−01 −7.40816E−02 A6 = 5.88593E−041.24941E−01 3.23760E−01 2.06880E−01 6.85023E−03 A8 = 3.42438E−021.21832E−01 −1.65624E−01 −2.09507E−01 5.65475E−02 A10 = −7.43772E−02−2.35714E−01 −3.21678E−01 3.69034E−02 −3.50569E−02 A12 = 7.09448E−02−4.32324E−01 4.45872E−01 −1.88130E−02 1.98610E−02 A14 = −7.92872E−038.63940E−01 −4.62328E−02 2.34558E−02 −4.60460E−03 Surface # 7 8 9 10 11k = 9.47271E−01 2.80851E+01 −3.95160E+00 −1.03679E+01 −1.01984E+01 A4 =−8.43459E−02 −9.65180E−02 −7.62128E−02 −4.05789E−02 −3.56431E−02 A6 =1.71494E−02 2.19387E−02 3.11470E−02 3.18188E−03 5.43609E−03 A8 =−7.09279E−03 −2.08083E−02 −1.27134E−02 1.71220E−03 −8.10968E−04 A10 =1.30660E−02 −1.35422E−04 7.65966E−04 −2.15950E−04 2.83940E−05 A12 =1.22688E−03 1.02710E−03 4.85624E−04 9.12256E−06 5.43291E−06 A14 =5.57775E−05 4.81718E−05 −2.40581E−05 −1.12423E−06 −2.92442E−07

The equation of the aspheric surface profiles of the second embodimenthas the same form as that of the first embodiment. Moreover, thedescription of the factors in the relations is as those set forth in thefirst embodiment, but the values of the relations of the secondembodiment are listed in the following TABLE 5.

TABLE 5 (Embodiment 2) f 4.35 (R9 + R10)/(R9 − R10) −0.26 Fno 2.85 R8/f−0.18 HFOV 33.1 f/f3 0.37 V1 − V2 34.9 f/f5 −3.58 CT4/CT5 3.74 |f/f4| +|f/f5| 6.43 (T23 + T34)/CT3 2.51 SD/TD 0.86 (R3 + R4)/(R3 − R4) 3.37TTL/ImgH 1.80

Embodiment 3

FIG. 3A shows an image capturing optical system in accordance with thethird embodiment of the present invention, and FIG. 3B shows theaberration curves of the third embodiment of the present invention. Theimage capturing optical system of the third embodiment of the presentinvention mainly comprises five lens elements, in order from an objectside to an image side:

a first lens element 310 made of plastic with positive refractive powerhaving a convex object-side surface 311 and a concave image-side surface312, the object-side and image-side surfaces 311 and 312 thereof beingaspheric;

a second lens element 320 made of plastic with negative refractive powerhaving a convex object-side surface 321 and a concave image-side surface322, the object-side and image-side surfaces 321 and 322 thereof beingaspheric;

a third lens element 330 made of plastic with positive refractive powerhaving a convex object-side surface 331 and a convex image-side surface332, the object-side and image-side surfaces 331 and 332 thereof beingaspheric;

a fourth lens element 340 made of plastic with positive refractive powerhaving a concave object-side surface 341 and a convex image-side surface342, the object-side and image-side surfaces 341 and 342 thereof beingaspheric; and

a fifth lens element 350 made of plastic with negative refractive powerhaving a concave object-side surface 351 and a concave image-sidesurface 352, the object-side and image-side surfaces 351 and 352 thereofbeing aspheric, and at least one inflection point is formed on both theobject-side surface 351 and the image-side surface 352 thereof;

wherein an aperture stop 300 is disposed between the first lens element310 and the second lens element 320;

the image capturing optical system further comprises an IR filter 360disposed between the image-side surface 352 of the fifth lens element350 and an image plane 371, and the IR filter 360 is made of glass andhas no influence on the focal length of the image capturing opticalsystem; the image capturing optical system further comprises an imagesensor 370 provided on the image plane 371.

The detailed optical data of the third embodiment is shown in TABLE 6,and the aspheric surface data is shown in TABLE 7, wherein the units ofthe radius of curvature, the thickness and the focal length areexpressed in mm, and HFOV is half of the maximal field of view.

TABLE 6 (Embodiment 3) f = 4.63 mm, Fno = 3.00, HFOV = 32.3 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # length 0Object Plano Infinity 1 Lens 1   1.729133 (ASP) 0.540 Plastic 1.514 56.83.72 2 16.442005 (ASP) 0.037 3 Ape. Stop Plano 0.080 4 Lens 2   3.265483(ASP) 0.286 Plastic 1.634 23.8 -6.50 5   1.760378 (ASP) 0.459 6 Lens 325.055158 (ASP) 0.430 Plastic 1.535 56.3 11.82 7  -8.400486 (ASP) 0.6208 Lens 4  -8.665761 (ASP) 1.189 Plastic 1.535 56.3 1.53 9  -0.781227(ASP) 0.179 10 Lens 5  -1.067010 (ASP) 0.317 Plastic 1.535 56.3 -1.21 11  1.825101 (ASP) 0.500 12 IR-filter Plano 0.300 Glass 1.517 64.2 — 13Plano 0.512 14 Image Plano — * Reference wavelength is d-line 587.6 nm

TABLE 7 Aspheric Coefficients Surface # 1 2 4 5 6 k = 8.62415E−014.92768E+00 1.34600E+00 2.07884E+00 −1.00000E+00 A4 = −1.32469E−02−5.46509E−02 −2.06564E−01 −2.11683E−01 −7.40763E−02 A6 = 5.96622E−041.24935E−01 3.23767E−01 2.06871E−01 6.85553E−03 A8 = 3.43119E−021.21815E−01 −1.65610E−01 −2.09521E−01 5.65525E−02 A10 = −7.43163E−02−2.35931E−01 −3.21635E−01 3.68795E−02 −3.50523E−02 A12 = 7.09845E−02−4.36056E−01 4.46849E−01 −2.03284E−02 1.98654E−02 A14 = −7.90063E−038.42290E−01 −3.78951E−02 2.30111E−02 −4.60460E−03 Surface # 7 8 9 10 11k = 9.70317E−01 2.80474E+01 −3.95144E+00 −1.03720E+01 −1.02215E+01 A4 =−8.43509E−02 −9.65149E−02 −7.62173E−02 −4.05754E−02 −3.56613E−02 A6 =1.71453E−02 2.19445E−02 3.11453E−02 3.18238E−03 5.43527E−03 A8 =−7.09585E−03 −2.08034E−02 −1.27140E−02 1.71228E−03 −8.11033E−04 A10 =1.30637E−02 −1.32114E−04 7.65809E−04 −2.15933E−04 2.83883E−05 A12 =1.22518E−03 1.02925E−03 4.85576E−04 9.12582E−06 5.43234E−06 A14 =5.57775E−05 4.95682E−05 −2.40731E−05 −1.12356E−06 −2.92508E−07

The equation of the aspheric surface profiles of the third embodimenthas the same form as that of the first embodiment. Moreover, thedescription of the factors in the relations is as those set forth in thefirst embodiment, but the values of the relations of the thirdembodiment are listed in the following TABLE 8.

TABLE 8 (Embodiment 3) f 4.63 (R9 + R10)/(R9 − R10) −0.26 Fno 3.00 R8/f−0.17 HFOV 32.3 f/f3 0.39 V1 − V2 33.0 f/f5 −3.81 CT4/CT5 3.75 |f/f4| +|f/f5| 6.84 (T23 + T34)/CT3 2.51 SD/TD 0.86 (R3 + R4)/(R3 − R4) 3.34TTL/ImgH 1.87

Embodiment 4

FIG. 4A shows an image capturing optical system in accordance with thefourth embodiment of the present invention, and FIG. 4B shows theaberration curves of the fourth embodiment of the present invention. Theimage capturing optical system of the fourth embodiment of the presentinvention mainly comprises five lens elements, in order from an objectside to an image side:

a first lens element 410 made of plastic with positive refractive powerhaving a convex object-side surface 411 and a concave image-side surface412, the object-side and image-side surfaces 411 and 412 thereof beingaspheric;

a second lens element 420 made of plastic with negative refractive powerhaving a convex object-side surface 421 and a concave image-side surface422, the object-side and image-side surfaces 421 and 422 thereof beingaspheric;

a third lens element 430 made of plastic with positive refractive powerhaving a concave object-side surface 431 and a convex image-side surface432, the object-side and image-side surfaces 431 and 432 thereof beingaspheric;

a fourth lens element 440 made of plastic with positive refractive powerhaving a convex object-side surface 441 and a convex image-side surface442, the object-side and image-side surfaces 441 and 442 thereof beingaspheric; and

a fifth lens element 450 made of plastic with negative refractive powerhaving a concave object-side surface 451 and a concave image-sidesurface 452, the object-side and image-side surfaces 451 and 452 thereofbeing aspheric, and at least one inflection point is formed on both theobject-side surface 451 and the image-side surface 452 thereof;

wherein an aperture stop 400 is disposed between an imaged object andthe first lens element 410;

the image capturing optical system further comprises an IR filter 460disposed between the image-side surface 452 of the fifth lens element450 and an image plane 471, and the IR filter 460 is made of glass andhas no influence on the focal length of the image capturing opticalsystem; the image capturing optical system further comprises an imagesensor 470 provided on the image plane 471.

The detailed optical data of the fourth embodiment is shown in TABLE 9,and the aspheric surface data is shown in TABLE 10, wherein the units ofthe radius of curvature, the thickness and the focal length areexpressed in mm, and HFOV is half of the maximal field of view.

TABLE 9 (Embodiment 4) f = 4.23 mm, Fno = 3.30, HFOV =33.4 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # length 0Object Plano Infinity 1 Ape. Stop Plano -0.115 2 Lens 1    1.692563(ASP) 0.526 Plastic 1.535 56.3 3.66 3   11.121373 (ASP) 0.103 4 Lens 2   3.034228 (ASP) 0.262 Plastic 1.633 23.4 -6.69 5    1.708375 (ASP)0.504 6 Lens 3 -175.078680 (ASP) 0.412 Plastic 1.535 56.3 14.48 7  -7.417758 (ASP) 0.690 8 Lens 4   50.000000 (ASP) 0.960 Plastic 1.53556.3 1.71 9    -0.924454 (ASP) 0.212 10 Lens 5    -0.967772 (ASP) 0.431Plastic 1.535 56.3 -1.34 11    3.220075 (ASP) 0.400 12 IR-filter Plano0.300 Glass 1.517 64.2 — 13 Plano 0.362 14 Image Plano — * Referencewavelength is d-line 587.6 nm

TABLE 10 Aspheric Coefficients Surface # 2 3 4 5 6 k = 8.64088E−01−4.58599E+01 −3.38650E−02 1.98002E+00 5.00000E+01 A4 = −1.28569E−02−5.77372E−02 −2.09549E−01 −2.03117E−01 −7.59005E−02 A6 = −1.33309E−031.14838E−01 3.01719E−01 2.05725E−01 5.85643E−03 A8 = 3.63338E−028.52022E−02 −1.76475E−01 −2.47215E−01 5.54235E−02 A10 = −8.91984E−02−2.02564E−01 −3.33498E−01 7.33910E−02 −3.25023E−02 A12 = 7.33844E−02−4.35565E−01 4.48465E−01 −2.21802E−02 1.99915E−02 A14 = 6.37080E−038.27201E−01 −2.39055E−02 1.44922E−02 −4.66865E−03 Surface # 7 8 9 10 11k = 5.93129E+00 4.57617E+01 −3.64824E+00 −5.04303E+00 −1.80045E−01 A4 =−8.54209E−02 −9.00664E−02 −8.16794E−02 −3.60234E−02 −5.14646E−02 A6 =1.70799E−02 2.28190E−02 3.27492E−02 3.16828E−03 5.91053E−03 A8 =−7.22990E−03 −1.62626E−02 −1.20968E−02 1.71655E−03 −7.72595E−04 A10 =1.20566E−02 1.63212E−03 8.62941E−04 −2.13999E−04 2.83937E−05 A12 =4.15047E−04 1.14987E−03 5.01526E−04 8.83016E−06 4.63551E−06 A14 =−5.45990E−05 −2.26131E−04 −2.03652E−05 −1.57191E−06 −4.80753E−07

The equation of the aspheric surface profiles of the fourth embodimenthas the same form as that of the first embodiment. Moreover, thedescription of the factors in the relations is as those set forth in thefirst embodiment, but the values of the relations of the fourthembodiment are listed in the following TABLE 11.

TABLE 11 (Embodiment 4) f 4.23 (R9 + R10)/(R9 − R10) −0.54 Fno 3.30 R8/f−0.22 HFOV 33.4 f/f3 0.29 V1 − V2 32.9 f/f5 −3.15 CT4/CT5 2.23 |f/f4| +|f/f5| 5.63 (T23 + T34)/CT3 2.90 SD/TD 0.97 (R3 + R4)/(R3 − R4) 3.58TTL/ImgH 1.77

Embodiment 5

FIG. 5A shows an image capturing optical system in accordance with thefifth embodiment of the present invention, and FIG. 5B shows theaberration curves of the fifth embodiment of the present invention. Theimage capturing optical system of the fifth embodiment of the presentinvention mainly comprises five lens elements, in order from an objectside to an image side:

a first lens element 510 made of plastic with positive refractive powerhaving a convex object-side surface 511 and a convex image-side surface512, the object-side and image-side surfaces 511 and 512 thereof beingaspheric;

a second lens element 520 made of plastic with negative refractive powerhaving a convex object-side surface 521 and a concave image-side surface522, the object-side and image-side surfaces 521 and 522 thereof beingaspheric;

a third lens element 530 made of plastic with negative refractive powerhaving a convex object-side surface 531 and a concave image-side surface532, the object-side and image-side surfaces 531 and 532 thereof beingaspheric;

a fourth lens element 540 made of plastic with positive refractive powerhaving a concave object-side surface 541 and a convex image-side surface542, the object-side and image-side surfaces 541 and 542 thereof beingaspheric; and

a fifth lens element 550 made of plastic with negative refractive powerhaving a concave object-side surface 551 and a concave image-sidesurface 552, the object-side and image-side surfaces 551 and 552 thereofbeing aspheric, and at least one inflection point is formed on both theobject-side surface 551 and the image-side surface 552 thereof;

wherein an aperture stop 500 is disposed between the first lens element510 and the second lens element 520;

the image capturing optical system further comprises an IR filter 560disposed between the image-side surface 552 of the fifth lens element550 and an image plane 571, and the IR filter 560 is made of glass andhas no influence on the focal length of the image capturing opticalsystem; the image capturing optical system further comprises an imagesensor 570 provided on the image plane 571.

The detailed optical data of the fifth embodiment is shown in TABLE 12,and the aspheric surface data is shown in TABLE 13, wherein the units ofthe radius of curvature, the thickness and the focal length areexpressed in mm, and HFOV is half of the maximal field of view.

TABLE 12 (Embodiment 5) f = 4.42 mm, Fno = 3.00, HFOV = 32.6 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # length 0Object Plano Infinity 1 Lens 1   2.020480 (ASP) 0.582 Plastic 1.535 56.33.38 2 -15.384600 (ASP) 0.102 3 Ape. Stop Plano -0.002 4 Lens 2  5.695600 (ASP) 0.250 Plastic 1.634 23.8 -6.80 5   2.412720 (ASP) 0.5836 Lens 3   9.990000 (ASP) 0.462 Plastic 1.634 23.8 -51.14 7   7.499900(ASP) 0.466 8 Lens 4 -16.535300 (ASP) 0.852 Plastic 1.535 56.3 1.56 9 -0.809830 (ASP) 0.210 10 Lens 5  -1.581540 (ASP) 0.282 Plastic 1.53556.3 -1.40 11   1.499360 (ASP) 0.500 12 IR-filter Plano 0.300 Glass1.517 64.2 — 13 Plano 0.719 14 Image Plano — * Reference wavelength isd-line 587.6 nm

TABLE 13 Aspheric Coefficients Surface # 1 2 4 5 6 k = 7.40670E−01−5.00000E+01 9.98154E+00 2.28059E+00 −2.00000E+01 A4 = −1.98576E−02−4.93972E−02 −1.97437E−01 −2.07642E−01 −8.69032E−02 A6 = 1.21634E−031.05901E−01 3.43247E−01 2.31853E−01 5.67844E−04 A8 = 3.83343E−021.46884E−01 −1.66052E−01 −2.27701E−01 4.69084E−02 A10 = −7.59112E−02−3.06051E−01 −3.66354E−01 7.82506E−02 −4.08987E−02 A12 = 1.57766E−02−4.48936E−01 4.29155E−01 −2.15686E−02 1.51424E−02 A14 = 3.22873E−028.52567E−01 −1.13058E−02 2.99640E−02 −4.60460E−03 Surface # 7 8 9 10 11k = 1.69325E+01 −2.21184E+01 −3.85555E+00 −1.50109E+01 −1.45461E+01 A4 =−8.08105E−02 −7.26724E−02 −7.30420E−02 −3.56401E−02 −4.05237E−02 A6 =2.16401E−02 2.91603E−02 3.85631E−02 3.39638E−03 5.53437E−03 A8 =−4.65644E−03 −1.78301E−02 −1.10840E−02 1.76931E−03 −8.43406E−04 A10 =1.14028E−02 1.15181E−03 8.92508E−04 −2.08588E−04 2.36937E−05 A12 =−2.90845E−03 1.31575E−03 4.31774E−04 8.51982E−06 5.98748E−06 A14 =5.57775E−05 2.11885E−04 −6.09681E−05 −2.28474E−06 2.55234E−07

The equation of the aspheric surface profiles of the fifth embodimenthas the same form as that of the first embodiment. Moreover, thedescription of the factors in the relations is as those set forth in thefirst embodiment, but the values of the relations of the fifthembodiment are listed in the following TABLE 14.

TABLE 14 (Embodiment 5) f 4.42 (R9 + R10)/(R9 − R10) 0.03 Fno 3.00 R8/f−0.18 HFOV 32.6 f/f3 −0.09 V1 − V2 32.5 f/f5 −3.17 CT4/CT5 3.02 |f/f4| +|f/f5| 6.00 (T23 + T34)/CT3 2.27 SD/TD 0.82 (R3 + R4)/(R3 − R4) 2.47TTL/ImgH 1.82

Embodiment 6

FIG. 6A shows an image capturing optical system in accordance with thesixth embodiment of the present invention, and FIG. 6B shows theaberration curves of the sixth embodiment of the present invention. Theimage capturing optical system of the sixth embodiment of the presentinvention mainly comprises five lens elements, in order from an objectside to an image side:

a first lens element 610 made of plastic with positive refractive powerhaving a convex object-side surface 611 and a concave image-side surface612, the object-side and image-side surfaces 611 and 612 thereof beingaspheric;

a second lens element 620 made of plastic with negative refractive powerhaving a convex object-side surface 621 and a concave image-side surface622, the object-side and image-side surfaces 621 and 622 thereof beingaspheric;

a third lens element 630 made of plastic with negative refractive powerhaving a convex object-side surface 631 and a concave image-side surface632, the object-side and image-side surfaces 631 and 632 thereof beingaspheric;

a fourth lens element 640 made of plastic with positive refractive powerhaving a concave object-side surface 641 and a convex image-side surface642, the object-side and image-side surfaces 641 and 642 thereof beingaspheric; and

a fifth lens element 650 made of plastic with negative refractive powerhaving a concave object-side surface 651 and a concave image-sidesurface 652, the object-side and image-side surfaces 651 and 652 thereofbeing aspheric, and at least one inflection point is formed on both theobject-side surface 651 and the image-side surface 652 thereof;

wherein an aperture stop 600 is disposed between the first lens element610 and the second lens element 620;

the image capturing optical system further comprises an IR filter 660disposed between the image-side surface 652 of the fifth lens element650 and an image plane 671, and the IR filter 660 is made of glass andhas no influence on the focal length of the image capturing opticalsystem; the image capturing optical system further comprises an imagesensor 670 provided on the image plane 671.

The detailed optical data of the sixth embodiment is shown in TABLE 15,and the aspheric surface data is shown in TABLE 16, wherein the units ofthe radius of curvature, the thickness and the focal length areexpressed in mm, and HFOV is half of the maximal field of view.

TABLE 15 (Embodiment 6) f = 4.44 mm, Fno = 3.00, HFOV = 32.5 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # length 0Object Plano Infinity 1 Lens 1   1.804009 (ASP) 0.524 Plastic 1.544 55.93.36 2 113.600087 (ASP) 0.050 3 Ape. Stop Plano 0.050 4 Lens 2  6.346443 (ASP) 0.250 Plastic 1.634 23.8 -6.99 5   2.569306 (ASP) 0.5606 Lens 3  10.272469 (ASP) 0.490 Plastic 1.634 23.8 -38.91 7   7.118337(ASP) 0.470 8 Lens 4  -19.029392 (ASP) 0.916 Plastic 1.544 55.9 1.49 9  -0.792057 (ASP) 0.196 10 Lens 5   -1.484695 (ASP) 0.280 Plastic 1.54455.9 -1.33 11    1.497125 (ASP) 0.500 12 IR-filter Plano 0.300 Glass1.517 64.2 — 13 Plano 0.694 14 Image Plano — * Reference wavelength isd-line 587.6 nm

TABLE 16 Aspheric Coefficients Surface # 1 2 4 5 6 k = 8.60551E−015.00000E+01 1.18679E+00 2.85522E+00 −2.00000E+01 A4 = −1.60172E−02−5.36724E−02 −2.05550E−01 −1.97878E−01 −8.89323E−02 A6 = 4.32136E−031.04231E−01 3.31699E−01 2.28309E−01 7.01936E−04 A8 = 3.77047E−021.51298E−01 −1.76025E−01 −2.45030E−01 4.74684E−02 A10 = −8.23865E−02−3.29860E−01 −3.98970E−01 8.37582E−02 −4.18770E−02 A12 = 5.15429E−02−4.43656E−01 4.29156E−01 −2.15686E−02 1.19403E−02 A14 = 8.10507E−048.52567E−01 −1.13058E−02 2.99640E−02 −4.60460E−03 Surface # 7 8 9 10 11k = 1.62696E+01 −4.86804E+01 −3.91946E+00 −1.40110E+01 −1.56266E+01 A4 =−8.15130E−02 −7.19781E−02 −7.15261E−02 −3.56895E−02 −4.00646E−02 A6 =2.12200E−02 2.87050E−02 3.81708E−02 3.40509E−03 5.48056E−03 A8 =−5.02386E−03 −1.82441E−02 −1.12650E−02 1.76919E−03 −8.33428E−04 A10 =1.12441E−02 9.83787E−04 8.51052E−04 −2.07794E−04 2.44574E−05 A12 =−2.94916E−03 1.26479E−03 4.21388E−04 8.97288E−06 6.16287E−06 A14 =5.57775E−05 2.08258E−04 −6.47436E−05 −2.16751E−06 2.93007E−07

The equation of the aspheric surface profiles of the sixth embodimenthas the same form as that of the first embodiment. Moreover, thedescription of the factors in the relations is as those set forth in thefirst embodiment, but the values of the relations of the sixthembodiment are listed in the following TABLE 17.

TABLE 17 (Embodiment 6) f 4.44 (R9 + R10)/(R9 − R10) 0.00 Fno 3.00 R8/f−0.18 HFOV 32.5 f/f3 −0.11 V1 − V2 32.1 f/f5 −3.34 CT4/CT5 3.27 |f/f4| +|f/f5| 6.32 (T23 + T34)/CT3 2.10 SD/TD 0.85 (R3 + R4)/(R3 − R4) 2.36TTL/ImgH 1.81

Embodiment 7

FIG. 7A shows an image capturing optical system in accordance with theseventh embodiment of the present invention, and FIG. 7B shows theaberration curves of the seventh embodiment of the present invention.The image capturing optical system of the seventh embodiment of thepresent invention mainly comprises five lens elements, in order from anobject side to an image side:

a first lens element 710 made of plastic with positive refractive powerhaving a convex object-side surface 711 and a concave image-side surface712, the object-side and image-side surfaces 711 and 712 thereof beingaspheric;

a second lens element 720 made of plastic with negative refractive powerhaving a convex object-side surface 721 and a concave image-side surface722, the object-side and image-side surfaces 721 and 722 thereof beingaspheric;

a third lens element 730 made of plastic with positive refractive powerhaving a concave object-side surface 731 and a convex image-side surface732, the object-side and image-side surfaces 731 and 732 thereof beingaspheric;

a fourth lens element 740 made of plastic with positive refractive powerhaving a concave object-side surface 741 and a convex image-side surface742, the object-side and image-side surfaces 741 and 742 thereof beingaspheric; and

a fifth lens element 750 made of plastic with negative refractive powerhaving a concave object-side surface 751 and a concave image-sidesurface 752, the object-side and image-side surfaces 751 and 752 thereofbeing aspheric, and at least one inflection point is formed on both theobject-side surface 751 and the image-side surface 752 thereof;

wherein an aperture stop 700 is disposed between the first lens element710 and the second lens element 720;

the image capturing optical system further comprises an IR filter 760disposed between the image-side surface 752 of the fifth lens element750 and an image plane 771, and the IR filter 760 is made of glass andhas no influence on the focal length of the image capturing opticalsystem; the image capturing optical system further comprises an imagesensor 770 provided on the image plane 771.

The detailed optical data of the seventh embodiment is shown in TABLE18, and the aspheric surface data is shown in TABLE 19, wherein theunits of the radius of curvature, the thickness and the focal length areexpressed in mm, and HFOV is half of the maximal field of view.

TABLE 18 (Embodiment 7) f = 4.20 mm, Fno = 2.85, HFOV = 34.5 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # length 0Object Plano Infinity 1 Lens 1   1.700670 (ASP) 0.516 Plastic 1.544 55.93.64 2  10.680800 (ASP) 0.050 3 Ape. Stop Plano 0.064 4 Lens 2  2.979900 (ASP) 0.250 Plastic 1.634 23.8 -6.84 5   1.708630 (ASP) 0.5136 Lens 3 -39.213400 (ASP) 0.401 Plastic 1.544 55.9 17.50 7  -7.690500(ASP) 0.558 8 Lens 4  -9.964300 (ASP) 0.833 Plastic 1.544 55.9 1.65 9 -0.849920 (ASP) 0.228 10 Lens 5  -1.442450 (ASP) 0.280 Plastic 1.54455.9 -1.39 11   1.698590 (ASP) 0.500 12 IR-filter Plano 0.300 Glass1.517 64.2 — 13 Plano 0.558 14 Image Plano — * Reference wavelength isd-line 587.6 nm

TABLE 19 Aspheric Coefficients Surface # 1 2 4 5 6 k = 8.38613E−01−3.05112E+01 −4.80408E−02 1.97799E+00 2.40506E+02 A4 = −1.43412E−02−5.60888E−02 −2.09727E−01 −2.02496E−01 −7.56867E−02 A6 = −1.40300E−031.11809E−01 3.08044E−01 2.06654E−01 6.60201E−03 A8 = 3.72223E−027.93690E−02 −1.62791E−01 −2.44818E−01 5.55997E−02 A10 = −8.58912E−02−1.95881E−01 −3.40311E−01 7.25977E−02 −3.25325E−02 A12 = 7.30630E−02−4.32284E−01 4.45844E−01 −1.88031E−02 2.00380E−02 A14 = −6.77788E−038.63941E−01 −4.62315E−02 2.34562E−02 −4.60460E−03 Surface # 7 8 9 10 11k = 6.36991E+00 1.89992E+01 −3.53695E+00 −9.95677E+00 −1.49360E+01 A4 =−8.52244E−02 −9.06096E−02 −7.76829E−02 −3.87547E−02 −4.05138E−02 A6 =1.58712E−02 2.60126E−02 3.21903E−02 3.07689E−03 5.30551E−03 A8 =−7.58848E−03 −1.72042E−02 −1.20811E−02 1.70863E−03 −8.19341E−04 A10 =1.21813E−02 1.10776E−03 9.08862E−04 −2.13987E−04 2.77001E−05 A12 =5.95033E−04 9.73596E−04 5.18028E−04 8.87147E−06 5.35976E−06 A14 =5.57775E−05 −2.66096E−04 −1.72111E−05 −1.59460E−06 −2.80410E−07

The equation of the aspheric surface profiles of the seventh embodimenthas the same form as that of the first embodiment. Moreover, thedescription of the factors in the relations is as those set forth in thefirst embodiment, but the values of the relations of the seventhembodiment are listed in the following TABLE 20.

TABLE 20 (Embodiment 7) f 4.20 (R9 + R10)/(R9 − R10) −0.08 Fno 2.85 R8/f−0.20 HFOV 34.5 f/f3 0.24 V1 − V2 32.1 f/f5 −3.02 CT4/CT5 2.98 |f/f4| +|f/f5| 5.56 (T23 + T34)/CT3 2.67 SD/TD 0.85 (R3 + R4)/(R3 − R4) 3.69TTL/ImgH 1.73

Embodiment 8

FIG. 8A shows an image capturing optical system in accordance with theeighth embodiment of the present invention, and FIG. 8B shows theaberration curves of the eighth embodiment of the present invention. Theimage capturing optical system of the eighth embodiment of the presentinvention mainly comprises five lens elements, in order from an objectside to an image side:

a first lens element 810 made of plastic with positive refractive powerhaving a convex object-side surface 811 and a convex image-side surface812, the object-side and image-side surfaces 811 and 812 thereof beingaspheric;

a second lens element 820 made of plastic with negative refractive powerhaving a concave object-side surface 821 and a concave image-sidesurface 822, the object-side and image-side surfaces 821 and 822 thereofbeing aspheric;

a third lens element 830 made of plastic with positive refractive powerhaving a convex object-side surface 831 and a convex image-side surface832, the object-side and image-side surfaces 831 and 832 thereof beingaspheric;

a fourth lens element 840 made of plastic with positive refractive powerhaving a concave object-side surface 841 and a convex image-side surface842, the object-side and image-side surfaces 841 and 842 thereof beingaspheric; and

a fifth lens element 850 made of plastic with negative refractive powerhaving a concave object-side surface 851 and a concave image-sidesurface 852, the object-side and image-side surfaces 851 and 852 thereofbeing aspheric, and at least one inflection point is formed on both theobject-side surface 851 and the image-side surface 852 thereof;

wherein an aperture stop 800 is disposed between the first lens element810 and the second lens element 820;

the image capturing optical system further comprises an IR filter 860disposed between the image-side surface 852 of the fifth lens element850 and an image plane 871, and the IR filter 860 is made of glass andhas no influence on the focal length of the image capturing opticalsystem; the image capturing optical system further comprises an imagesensor 870 provided on the image plane 871.

The detailed optical data of the eighth embodiment is shown in TABLE 21,and the aspheric surface data is shown in TABLE 22, wherein the units ofthe radius of curvature, the thickness and the focal length areexpressed in mm, and HFOV is half of the maximal field of view.

TABLE 21 (Embodiment 8) f = 4.49 mm, Fno = 2.85, HFOV = 32.4 deg. FocalSurface # Curvature Radius Thickness Material Index Abbe # length 0Object Plano Infinity 1 Lens 1  2.120513 (ASP) 0.514 Glass 1.548 45.72.99 2 -6.617692 (ASP) 0.050 3 Ape. Stop Plano 0.056 4 Lens 2 -28.901734(ASP) 0.322 Plastic 1.634 23.8 -4.10 5   2.867103 (ASP) 0.571 6 Lens 3  5.937584 (ASP) 0.429 Plastic 1.544 55.9 8.36 7 -18.979522 (ASP) 0.8738 Lens 4  -8.867389 (ASP) 0.973 Plastic 1.544 55.9 1.39 9  -0.724964(ASP) 0.050 10 Lens 5  -1.861135 (ASP) 0.416 Plastic 1.535 56.3 -1.07 11  0.894534 (ASP) 0.550 12 IR-filter Plano 0.300 Glass 1.517 64.2 — 13Plano 0.373 14 Image Plano — * Reference wavelength is d-line 587.6 nm

TABLE 22 Aspheric Coefficients Surface # 1 2 4 5 6 k = 7.09009E−01−1.75995E+01 −5.00000E+01 4.44429E+00 −5.00000E+01 A4 = −1.28709E−02−4.90738E−02 −1.53310E−01 −1.73256E−01 −7.59628E−02 A6 = −1.78431E−021.05440E−01 3.52326E−01 2.46889E−01 8.74262E−03 A8 = 2.85042E−03−3.61364E−02 −3.32274E−01 −2.61516E−01 3.41803E−02 A10 = 1.64335E−02−1.56180E−01 7.31004E−03 1.52674E−01 −4.19148E−02 A12 = −2.73584E−021.38384E−01 1.47237E−01 −7.44427E−02 4.02997E−02 A14 = −5.97038E−03−3.21924E−02 −4.62316E−02 2.34564E−02 −1.25716E−02 Surface # 7 8 9 10 11k = 2.00000E+01 −2.76431E+00 −4.67299E+00 −1.58711E+01 −9.19139E+00 A4 =−9.27772E−02 −9.25152E−02 −8.15721E−02 −6.30754E−02 −3.49447E−02 A6 =2.61856E−02 1.82507E−02 2.64045E−02 4.17828E−03 6.33295E−03 A8 =−1.15699E−02 −2.46724E−02 −1.45054E−02 1.98755E−03 −9.16376E−04 A10 =1.12377E−02 7.16742E−04 6.83661E−04 −1.95861E−04 1.47506E−05 A12 =1.74124E−03 2.76746E−03 5.65811E−04 1.05854E−05 6.01923E−06 A14 =−1.53778E−04 −2.72596E−04 4.14326E−05 −9.30753E−07 −2.45432E−07

The equation of the aspheric surface profiles of the eighth embodimenthas the same form as that of the first embodiment. Moreover, thedescription of the factors in the relations is as those set forth in thefirst embodiment, but the values of the relations of the eighthembodiment are listed in the following TABLE 23.

TABLE 23 (Embodiment 8) f 4.49 (R9 + R10)/(R9 − R10) 0.35 Fno 2.85 R8/f−0.16 HFOV 32.4 f/f3 0.54 V1 − V2 21.9 f/f5 −4.18 CT4/CT5 2.34 |f/f4| +|f/f5| 7.41 (T23 + T34)/CT3 3.36 SD/TD 0.87 (R3 + R4)/(R3 − R4) 0.82TTL/ImgH 1.88

It is to be noted that TABLES 1-23 show different data of the differentembodiments, however, the data of the different embodiments are obtainedfrom experiments. Therefore, any image capturing optical system of thesame structure is considered to be within the scope of the presentinvention even if it uses different data. The embodiments depicted aboveand the appended drawings are exemplary and are not intended to limitthe scope of the present invention.

1. An image capturing optical system comprising, in order from an objectside to an image side: a first lens element with positive refractivepower having a convex object-side surface; a second lens element; athird lens element; a fourth lens element with both the object-side andimage-side surfaces thereof being aspheric, and the fourth lens elementis made of plastic; and a fifth lens element with negative refractivepower, both the object-side and image-side surfaces thereof beingaspheric, at least one inflection point is formed on at least one of theobject-side and image-side surfaces thereof, and the fifth lens elementis made of plastic; wherein a focal length of the image capturingoptical system is f, a focal length of the fifth lens element is f5, andthey satisfy the following relation:−5.0<f/f5<−3.0.
 2. The image capturing optical system according to claim1, wherein the fifth lens element has a concave image-side surface. 3.The image capturing optical system according to claim 2, wherein thesecond lens element has negative refractive power and the fifth lenselement has a concave object-side surface.
 4. The image capturingoptical system according to claim 3, wherein a curvature radius of theobject-side surface of the second lens element is R3, a curvature radiusof the image-side surface of the second lens element is R4, and theysatisfy the following relation:1.5<(R3+R4)/(R3−R4)<4.5.
 5. The image capturing optical system accordingto claim 3, wherein the fourth lens element has positive refractivepower and has a convex image-side surface, the focal length of the imagecapturing optical system is f, a focal length of the third lens elementis f3, and they satisfy the following relation:−0.5<f/f3<0.5.
 6. The image capturing optical system according to claim5, wherein a central thickness of the fourth lens element is CT4, acentral thickness of the fifth lens element is CT5, and they satisfy thefollowing relation:2.5<CT4/CT5<4.5.
 7. The image capturing optical system according toclaim 5, wherein a curvature radius of the image-side surface of thefourth lens element is R8, the focal length of the image capturingoptical system is f, and they satisfy the following relation:−0.25<R8/f<−0.05.
 8. The image capturing optical system according toclaim 2, further comprising a stop, an axial distance between the stopand the image-side surface of the fifth lens element is SD, an axialdistance between the object-side surface of the first lens element andthe image-side surface of the fifth lens element is TD, and they satisfythe following relation:0.75<SD/TD<1.1.
 9. The image capturing optical system according to claim8, further comprising an image sensor provided on an image plane, anaxial distance between the second lens element and the third lenselement is T23, an axial distance between the third lens element and thefourth lens element is T34, a central thickness of the third lenselement is CT3, an axial distance between the object-side surface of thefirst lens element and the image plane is TTL, half of a diagonal lengthof an effective photosensitive area of the image sensor is ImgH, andthey satisfy the following relations:2.0<(T23+T34)/CT3<4.0; andTTL/ImgH<2.0.
 10. The image capturing optical system according to claim8, wherein an Abbe number of the first lens element is V1, an Abbenumber of the second lens element is V2, and they satisfy the followingrelation:30<V1−V2<42.
 11. The image capturing optical system according to claim1, wherein the second lens element has negative refractive power, andthe fourth lens element has positive refractive power.
 12. The imagecapturing optical system according to claim 11, wherein the focal lengthof the image capturing optical system is f, the focal length of thefifth lens element is f5, and they satisfy the following relation:−4.5<f/f5<−3.2.
 13. The image capturing optical system according toclaim 11, wherein the fourth lens element has a convex image-sidesurface, and the object-side surfaces and image-side surfaces of thefirst lens element, the second lens element and the third lens elementare all aspheric.
 14. The image capturing optical system according toclaim 13, wherein the second lens element has a convex object-sidesurface and a concave image-side surface; the fourth lens element has aconcave object-side surface; and the fifth lens element has a concaveobject-side surface and a concave image-side surface.
 15. The imagecapturing optical system according to claim 13, wherein the first lenselement, the second lens element and the third lens element are made ofplastic, the focal length of the image capturing optical system is f, afocal length of the fourth lens element is f4, the focal length of thefifth lens element is f5, and they satisfy the following relation:5.0<|f/f4|+|f/f5|<8.0.
 16. The image capturing optical system accordingto claim 13, wherein a curvature radius of the object-side surface ofthe fifth lens element is R9, a curvature radius of the image-sidesurface of the fifth lens element is R10, and they satisfy the followingrelation:−0.8<(R9+R10)/(R9−R10)<0.4.
 17. The image capturing optical systemaccording to claim 13, wherein a curvature radius of the image-sidesurface of the fourth lens element is R8, the focal length of the imagecapturing optical system is f, and they satisfy the following relation:−0.25<R8/f<−0.05.
 18. The image capturing optical system according toclaim 17, wherein a central thickness of the fourth lens element is CT4,a central thickness of the fifth lens element is CT5, and they satisfythe following relation:2.5<CT4/CT5<4.5.
 19. The image capturing optical system according toclaim 12, further comprising an image sensor provided on an image plane,an axial distance between the object-side surface of the first lenselement and the image plane is TTL, half of a diagonal length of aneffective photosensitive area of the image sensor is ImgH, and theysatisfy the following relation:TTL/ImgH<2.0.
 20. The image capturing optical system according to claim12, wherein the focal length of the image capturing optical system is f,the focal length of the fifth lens element is f5, and they satisfy thefollowing relation:−4.5<f/f5<−3.4.
 21. An image capturing optical system comprising, inorder from an object side to an image side: a first lens element withpositive refractive power having a convex object-side surface; a secondlens element with negative refractive power; a third lens element; afourth lens element with positive refractive power, a convex image-sidesurface, both the object-side and image-side surfaces thereof beingaspheric, and the fourth lens element is made of plastic; and a fifthlens element with negative refractive power, a concave image-sidesurface, both the object-side and image-side surfaces thereof beingaspheric, at least one inflection point is formed on at least one of theobject-side and image-side surfaces thereof, and the fifth lens elementis made of plastic; wherein a focal length of the image capturingoptical system is f, a focal length of the fifth lens element is f5, andthey satisfy the following relation:−5.0<f/f5<−3.0.
 22. The image capturing optical system according toclaim 21, wherein a curvature radius of the image-side surface of thefourth lens element is R8, the focal length of the image capturingoptical system is f, and they satisfy the following relation:−0.25<R8/f<−0.05.
 23. The image capturing optical system according toclaim 22, wherein the first lens element, the second lens element andthe third lens element are made of plastic, the focal length of theimage capturing optical system is f, a focal length of the fourth lenselement is f4, the focal length of the fifth lens element is f5, andthey satisfy the following relation:5.0<|f/f4|+|f/f5|<8.0.
 24. The image capturing optical system accordingto claim 22, wherein the focal length of the image capturing opticalsystem is f, the focal length of the fifth lens element is f5, and theysatisfy the following relation:−4.5<f/f5<−3.2.